Transformer network



Feb. 8, 1949.

I TRANSFORMER NETWORK R. G. STEPHENSON ET AL 2,

Filed Aug. 28, 1945 SUI/RC5 INVENTORS Q's/20rd 6.5fsp/7e/1s0n BY IW/fam M. Bush ATTORNEY Patented Feb. 8, 1949 UNITED STATES iATENT 2,461,091 ()F F I CE TRANSFORMER NETWORK Application August 28, 1945, Serial No. 613,178

(Cl. I'll-97) 6 Claims.

This invention relates to an electrical system or transformer network for use in electronic or electrical circuits.

It will be understood that, in the description which follows, the term signal is used in the sense in which it is normally used by those skilled in the arts of communications or electronics. Thus, the term signal is used to connote an alternating current (or voltage) which may convey intelligence by variation with time of its amplitude, frequency, or relative phase angle, or any combination of these. Also, the expression input signals is used to connote the (two or more) signals presented to the network of the present invention, and the expression output signals is used to connote the signals available from said network for utilization.

The object of this invention is to provide a novel transformer network by means of which a plurality of incoming signals, carried in individual channels, may be combined to produce simultaneously a multiplicity of outgoing signals carried in individual channels.

Another object of this invention is to provide a transformer circuit or network in which a selection of one or more of a plurality of output signals are available from the secondaries of the trans formers, proportional to the individual or com-- hined input signals in the primaries of the trans formers.

Another object is to provide a system of coupling transformers employing novel interccnnections of secondary coils for yielding a plurality of output signals bearing different relationships to each of a pair of input signals applied to individual ones of the transformer primar coils.

Further objects and advantages of this invention, as well as its construction, arrangement and operation, will be apparent from the following description and claims in connection with the companying drawing, in which there is shown a preferred form of the transformer network or circuit.

In the drawing there is shown two transformers generally designated as l and 2 respectively. Transformer l comprises a core 4 on which there is wound a primary coil 3 and a plurality of individual secondary windings 5 and 5 respectively. Secondary coil 5 of the transformer terminates at terminals '8 and 8, while secondary coil S of transformer I terminates in a pair of terminals 9 and I 0.

The transformer 2 consists of a primary coil H and a multiple number of individual secondary windings l2 and i3 respectively wound upon core 22. These coils l2 and I3 terminate at terminals l4-l5 and lii l'l, respectively.

The primary coils 3, l l may be energized by alternating-current signals derived from any suitable sources, here shown as source 3! and source 3 2 respectively connected to coils 3 and ii The secondary coils of the transformers are interconnected as shown in the drawing to provide a plurality of different output signals. Specifically, secondary coil 0 of transformer l is connected in additive series relation with coil l3 of conductorZS. Sec ondary winding 6 of transformer l is connected in diiierentiai series with secondary coil 52 of transformer 2 by means of conductor One end of each of secondary coils 6 and i3 res; ectively are connected to a common line such as represented by the ground connections 2 l2 l in the drawing. One end of each of coils 5, i5, i2 and i3 are connected to corresponding terminals !8, i9, 28 and 2i respectively.

The ratio of turns between the respective secondary and primary coil windings on each transformer determine the magnitude of the output voltage or signal on each of the s condary windings so that the output of each secondary winding can be made equal to, less than, or greater than the signal input to each transformer primary, as desired.

It will be seen that upon excitation by a suitable varying current signal from source 3i, the primary coil 3 of transformer i is flux-linked or inductively coupled with the secondary coils :"i and ii. Similarly, upon excitation by suitable vary" ing-current signal from source the primary coil ll of transformer 2 is fiux linked with the secondary coils l2 and i3.

Accordingly, the output signal from each of the secondary coils 5 E of transformer l, measured at the terminals 'li% and 9-Es respectively has a definite magnitude dependent on t e transformer ratio and the input signal to the ary. Similarly the output signal from each of t..e secondary coils l2 and $3 or" transformer as '.1easured across terminals i i s-? resoectively is determined by the to rimary coil ll.

By virtue of the connectin leads and the common connection t l, he output signals of the individual secondary i tapped individually or combined in the following manner.

Secondary winding 5 of transforms. l additive series relation with winding 53 of transformer 2 delivers the vector sum of the individual outputs of these coils at terminal it, if a load 33 or indicating device is connected to IE3 and to the common line 2 This output in turn is proportional to the vector sum of the input signals applied to the primaries oi the transformers. For balanced transicrmer operation, with the signals in phase, the oi he outputs of windings i3 is proportional to the sum of the inputs to each. transformer.

The output signal derived between terminal i9 and ground and applied to load 34 consists of the output of secondary coil 5 of transformer i spect to each other or connected in series with opposite polarity. Ihus, the output signal derivedbetween terminal 2% and gr und is proportional to the vector difference between the input signals applied to each of the primaries of transformers E and 2 respectively. For balanced transformer operation with the signals in phase, the above described outputs are proportional to the difference between the inn is to each transformer.

The output signal derived between terminal 2i and ground and applied to load 36 consists of the output of secondary coil is of transformer 2 alone, and is proportional to the input signal to the primary coil ii of transformer 2.

The operation of the invention may be summarized as follows:

The voltage at terminal is is proportional to the sum of the inputs to transformers l and 2,

The voltage at terminal is is proportional to theinput of transformer i only,

The voltage at terminal .26 is proportional to the difference between inputs to the transformers l and 2,

The voltage at terminal is proportional the input of transformer alone.

From the above it clear that two incoming signals are combined to produce four outgoing signals simultaneously and that oe or more of the four outgoing signals prod-...=ceri can be separately utilized.

By varying the number secondary wi? dings shown and described it is obvious that a still further optional number of signal outputs can be obtained in the manner described by using the network or circuit connection shown.

It is to be understood that various modifications and changes may be made in this invention without departing from the spirit and scope thereof as set forth in the appended claims;

What is claimed is:

1. In combination, a plurality of transformers each comprising a primary winding and a plurality of secondar windings, each of said primary windings being adapted to be energized from a separate source of alternating-current energy, and means interco cting said secondary windings of one of said transformers with secondary windings of the other of said transformers and for providing a plurality of terminals havin diiferent electrical characteristics.

2. In combination, a plurality of transforr each having a primary coil and a plurality of secondary coils, each of said primary coils being adapted to be energized from a separate source of alternating current energy, and means connecting one end of one of said secondar coils of one transformer to an output terminal connecting its other end to another output terminal and to one end of a secondary coil of a second transformer, means connecting the other end of said secondary coil of said second transformer to a common return circuit, a connection between one end of the other secondary coil of said first mentioned transformer and a common return cir cult, a second connection between the other end of said other secondary coil of said first-mentioned transformer and an output terminal and to one end of a .second secondary coil of said second-mentioned transformer, and means conmeeting the other end of said secondary coil of said second-mentioned transformer to an output terminal.

3. Electrical apparatus, comprising a plurality of transformers each having primary coils and a plurality of secondary coils, the secondary coils of each said transformer being adapted, upon simultaneous cophasal energization of the respective primary coils, to be characterized by similar cophasal relationships, conductive means connecting one secondary coil of one of said transformers to one secondary coil of another of said transformers in mutual series aiding relationship, and additional conductive means connecting another secondary coil of said one transformer to another secondary coil of said other transformer in mutual series opposing relationship, whereby an output signal is derived from said one secondary coil of said one transformer corresponding to the sum of said primary coil energizations and an outputsignal is derived from said other secondary coil of said other transformer corresponding to the difference of said primary coil energization.

4. The apparatus defined in claim 3 further characterized by means connected to the other secondary coil of aid one transformer for providing an output signal corresponding to one of said primary coil energizations and means connected to the other secondary coil of said other transformer for provi ing an output signal corresponding to the other of said primary coil energizations, said plurality of output signals being simultaneously derivable.

5. f'he apparatus defined in claim 3 further characterized by a first source of energization potential coupled to one of said primar coils and a second source of 'energization potential coupled to the other one of said primary coils.

6. Electrical transformer apparatus for converting a two-channel network into a four-channel network, comprising a first transformer having a first primary coil and a first pair of secondary coils, a second transformer having a sec ond primary coil and a second pair of secondary coils, a first source of alternating-current signals coupled to said first primary coil to energize said first primary coil with a first signal voltage, a second source of alternating-current signals coupled to said second primary coil to energize said second primary coil with a second signal voltage, individual loads connected to individual ones of each of said secondary coils at a first terminal of each of said secondary coils, means connecting a second terminal of one of said first pair of secondary coils and said first terminal of one of said second pair of secondary coils, means connecting said first terminal of the other of said first pair of secondary coils and a second terminal of the other of said second pair of secondary coils, and means connecting the second terminal of said other of said first pair of secondary coils and the second terminal of the said one of said second pair of secondary coils to ground.

RICHARD G. STEPHENSON. WELLIAM M. BUSH.

REFEBENGES CITED Date Re. 15,951

Dessauer Nov. I8, 1924' 

